Jeff McLane and Zach Berman

The ax fell first on Johnnie Lynn.

Could it fall again, and if so, who will it descend upon next?

The Eagles announced Saturday that they "released" Lynn not long after CBSportsline.com initially reported that the secondary coach was out. It is unclear when Andy Reid relieved Lynn of his duties, although the Eagles coach has been conducting exit interviews with his staff over the last week.

The Eagles aren't expected to make changes within their offensive coaching staff, but there could be additional moves made on the defensive side of the ball, a source close to the situation said.

The future of Juan Castillo remains the most speculated upon. The defensive coordinator isn't likely to be fired but could be shuffled into another post, perhaps as Lynn's replacement.

That would conceivably pave the way for Steve Spagnuolo to return to the Eagles as defensive coordinator. Spagnuolo, a former defensive assistant under Reid, was fired by the Rams on Monday after three years as their head coach.

It's unclear if the Eagles are even interested in Spagnuolo. Reid hasn't publicly spoken since immediately after the Eagles ended their season a disappointing 8-8 last Sunday. He won't meet with the media until he has made all of his staffing decisions.

Lynn, who previously coached for the 49ers, Ravens, Giants and Buccaneers, lasted all of one season with the Eagles. He was brought aboard last February as Reid remade his defensive coaching staff in the wake of defensive coordinator Sean McDermott's firing.

Lynn replaced Dick Jauron, who took the defensive coordinator job in Cleveland. Mike Zordich was promoted to oversee the safeties with Lynn in charge of the cornerbacks. Despite having three Pro Bowl corners in Nnamdi Asomugha, Asante Samuel and Dominique Rodgers-Cromartie, Lynn's unit did not live up to expectations.

Still, the problems in the secondary appeared to be more scheme-related. Asomugha played more zone defense that he ever had in Oakland. Samuel's ball-hawking abilities were neutralized by less blitzing. And Rodgers-Cromartie had never played in the slot until this season.

The Eagles defense allowed 27 passing touchdowns a season after surrendering 31. Cornerbacks accounted for only six total interceptions.

The cornerbacks weren't the only ones to struggle under Castillo in his first year as coordinator. The linebackers, under first-year coach Mike Caldwell, were not equipped to take on additional run-stopping responsibilities because of the new alignment up front.

Defensive line coach Jim Washburn had a successful season if his performance is judged by his unit's 46 sacks. But Washburn and his unique wide-nine may not mesh with Spagnuolo's scheme if the former Giants defensive coordinator is indeed hired.